Shark believed to have injured 4 people in waters off South Padre ...

Four people are believed to have been injured by the same shark while in waters off the southern coast of Texas on the Fourth of July, officials said.

Texas Game Warden Capt. Chris Dowdy told ABC Weslaco, Texas, affiliate KRGV that four separate incidents involving the shark, including two bites, were reported off South Padre Island.

In one of the incidents, the South Padre Island Police Department said it received a call reporting a "severe" shark bite to the leg at around 11 a.m. local time Thursday near the 4100 block of Gulf Boulevard.

First responders from the South Padre Island police and fire departments provided treatment at the scene before the man was transported to Valley Regional Medical Center in Brownsville, police said.

Footage from a beachgoer who witnessed the incident showed a shark swimming near the shore in the vicinity of that attack.

A second person was bitten by the shark, while one was grazed and another injured fending off the shark, Dowdy told KRGV.

The second bite victim was also taken to Valley Regional Medical Center in Brownsville. One of the two bite victims was flown out for "further treatment," Police said Thursday night.

Officials had previously said four separate shark bites were reported before later clarifying the nature of the incidents.

The shark has escaped to open waters and there is no plan to contain the shark at this time, Dowdy told the station.

The South Padre Island Beach patrol, along with the fire and police departments, were patrolling the shoreline and using drones, police said following the Thursday morning attack.

"Shark encounters of this nature are not a common occurrence in Texas," officials said in a statement. "When bites from sharks do occur, they are usually a case of mistaken identity by sharks looking for food."

Authorities have advised beachgoers that if they see "large schools of bait near the shore, this typically an indicator a predator is nearby, or if you see a shark in the water, calmly exit the water and wait for the predatory wildlife to pass."

This story has been updated.